1. Field of the Invention
The present invention relates to a channel access method in a wireless network, and more particularly, to a channel access method in a wireless network in which a channel access opportunity is provided to high priority traffic for each super-frame.
2. Description of the Related Art
Recently, a wireless network has been widely used due to ease of communications, data transmission, or the like, between objects.
In particular, a wireless network according to the IEEE 802.15.4 standard, having low power characteristics while satisfying low speed data transmission characteristics, or a wireless network using Zigbee has been widely used.
Meanwhile, in accordance with an increase in general societal interest in saving energy, a smart grid technology has been prominent. A smart grid, an intelligent power network in which an information-communication technology is grafted onto an existing power network, is a technology for maximizing energy efficiency through a real-time bi-directional information exchange between a power supplier and a power consumer. To this end, a wireless network device such as a smart utility network (SUN) according to the IEEE 802.15.4e standard or a wireless network device using Zigbee has been widely used.
In a frame structure in the IEEE 802.15.4e standard or the IEEE 802.15.4 standard, a time between two continuous beacons may be divided into an active period and an inactive period, and the active period may be again divided into a contention access period (CAP) in which transmission requests are contested and a contention free period (CFP) in which data is transmitted.
As described above, in the case of the channel access method according to the related art, terminals gaining access to the CAP gain the access regardless of traffic priority, such that the transmission of high priority traffic may be delayed.